Rationale for Symposium In 1802, Pliny Moody ploughed up a slab bearing footprints, on his father's farm. Some 35 years later, Edward Hitchcock, Professor at Amherst College (Amherst, Mass.) began describing these and other footprints discovered in the Connecticut Valley. This proposed symposium is intended to pay homage to Moody and Hitchcock, and illustrate current ichnological research.

Proposal

Timeliness of symposium

In 1802, a slab containing Early Jurassic age fossil footprints was plowed up on a farm in the Connecticut Valley of Massachusetts, and used as a doorstep. While not the subject of scientific study for some 35 years, it is the earliest verifiable record of footprints being excavated and preserved as geologic curiosities - indeed, the footprints were jokingly attributed to "Noah's Raven" by the farmer (Pliny Moody) and his neighbors. Prior to this, some footprint-bearing slabs had been used as paving stones, but the tracks were not recognized as such until the 1830's. We consider the year 2002 - the 200th anniversary of this discovery - to be a historically significant opportunity to present the results of modern ichnological research, although we limit the scope of the proposed symposium to vertebrate locomotory traces.

Need for symposium

The science of vertebrate paleoichnology has always been a multidisciplinary field bridging both geology and biology. Vertebrate paleoichnology is primarily perceived as the study of fossil footprints, but includes other "traces" of life - for example, the studies of coprolites, nests and eggs, and feeding-related traces (tooth marks and gastroliths). Footprints and other traces can be used both on their own, and to compliment data from the skeletal fossil record. Footprints in particular, being in situ remains, contribute significantly to our understanding of ancient terrestrial ecosystems. In addition, footprints reveal information on the dynamics of locomotion in extinct animals that is not revealed by skeletal material.

Although the study of vertebrate footprints has been ongoing for 165 years, it has been revitalized in the last two decades. Ichnological studies have expanded away from simple site descriptions, now using the data to help answer geologic and biologic questions. We believe a footprint symposium would be invaluable to nearly the entire Society membership: as a "group", footprints span the Devonian to Pleistocene, encompass the entire Vertebrata, and occur on every continent. There has not previously been an ichnological symposium at Society meetings, and we consider current research should be illustrated to the membership as a whole. In fact, the only previous symposium dedicated solely to ichnology was held 15 years ago in Albuquerque! We consider this symposium, in 2002, to be an ideal forum in which to present current research on all aspects of fossil footprints. The following table illustrates the increase in ichnologically-oriented presentations at SVP over the last 5 years:

Footprint research runs the gamut from biological to geological in focus. In biological studies, footprints have been used to contribute to our understanding of organisms (locomotion, functional anatomy, metabolism) and ecosystems (community structure, behavior). Geologically, the substrate on which tracks are impressed reveals information on the physical environment, from the local scale (for example, facies interpretations) to the regional scale (paleoclimate). Oftentimes, facies suitable for footprint preservation - for example, lake shorelines - rarely preserve skeletal material (and vice versa, e.g. fluvial channels); thus footprints can contribute to our knowledge of the fauna where skeletal remains are rare or absent. In other depositional settings - e.g. eolian systems - both tracks and bones can be preserved, footprints thus augmenting information gained from body fossils. On a larger scale footprints can be considered proxies for skeletal taxa, and used for biostratigraphy and biogeography. The value of this lies in the level to which trackmaker affinity can be determined. The participants of this symposium collectively will consider all of these ichnological facets.

Current organizational progress

To date, we have been in contact with approximately 40 workers, most of whom have expressed an interest in participating in the symposium. We have included a list of proposed participants, and their titles, at the end of this document. We have had far more response than we anticipated, and request that perhaps a poster session could be run concurrently (all day Wednesday) in conjunction with the oral presentations, in order to include as many contributions as possible!

We have a great diversity of proposed topics, including ichnotaxonomy and trackmaker identification, paleoecology, taphonomy, trackmaker behaviour, biostratigraphy, and biogeography. The contributions span wide geographic (North and South America, Asia, Europe) and temporal (Carboniferous - Tertiary) ranges, and include the four major clades of vertebrates (fish, amphibians, mammals, reptiles). In soliciting contributions, we have stressed from the outset that we prefer topics that use footprint data to address geologic and/or biologic issues, rather than preliminary site descriptions.

Information pertinent to the symposium can be found on a website created specifically for the purpose (http://ichno2002.freeservers.com), which will be maintained by Rainforth. At present the website has basic information only; we would like to be able to include the abstracts when they are accepted. This website will be a major communication tool between the participants.

Finally, Rainforth and McCrea have approached Indiana University Press, with a view to editing a volume that will include many of the contributions in this symposium, as well as some from workers who expressed an interest but are unable to attend SVP 2002 (e.g. Jim Farlow, Hartmut Haubold). A formal proposal is pending, but the concept has been favorably received by both IUP and the participants.